Inside casing cutter



April 21, 1931. E. GRAY INSIDE CASING CUTTER Filed Sept. 11, 1928 fi'g 5.

z g/Wgnwntoz Y means of advising the operator that the cut Patented Apr. 21, 1931 PATENT OFFICE ELLSWORTH GRAY, yOF HOUSTON, TEXAS,

JQ'SSIGNOlEt TO GRAY TOOL COMPANY, OF

HOUSTON, TEXAS, .A CORPORATION OF TEXAS INSIDE CASING CUTTER Application filed September 11, 1928. Serial No. 305,244.

My invention relates to that type of tool used to sever a pipe by inserting the tool therein and rotating either the pipe or the tool whereby an outstanding projection on the tool engages and cuts the pipe.

It is an object of my invention to provide a compact simplified tool which has a minimum number of moving parts, and is formed of a sturdy construction adapted to withstand the rough usage encountered in` this type oit work.

Another object is to construct a cutting tool which is constantly forced into engagement with the casing, thus obtaining a cut within a minimum of time.

A further obj ect is to arrange a simplified has been completed.

A still further object of my improvement is to so form the cutting blade that it may be readily renewed and is not liable to become broken or displaced.

rlhe most general use for tools of the type here disclosed occurs in removing the casing from wells. This casing is placed when the well is drilled to prevent the well bore from caving in and to keep out water or other foreign duide. rThis casing, due to corrosion and caving in, is usually wedged tightly in the well bore and cannot be removed as a unit. My tool may thus be lowered inside ot the casing to any desired point and the casing severed so that short lengths may then be removed.

@ther objects of my invention will be readily apparent to those skilledin the art to which my improvement appertains when the following description is considered in connection with the drawing, wherein Fig. 1 shows a vertical section thru the center/of my improved cutter showing the parts in the position they assume when the cut is completed. f

Fig. 2 is a cross-section taken on the line 2-2 of Fig. 3 and shows the operation of the cutting blade.

Fig. 3 is an elevation of the central portion of the tool.

Attention is directed to Fig. 1 of the drawing where the numeral 10 indicates the casing which is to be severed, and 11 represents the body of my improved tool in the position it i will occupy at the completion of the cut. This body 11 may be of steel or suitable metal and is preferably pointed or coneeshaped at 12 to facilitate its insertion into the casing. T he upper end of the body 11 has a cavity 13 formed therein which may be threaded as at 14 to receive a drill stem or other string of operating tubing 15 by means of which the body 11 may be rotated.

rTransverselyot the body 11 and above the taper point 12,1 have shown a bore 16 drilled from one side ot the body, and a co-axial bore 17 of less depth than 16 drilled in from the opposite side. These two bores form a hole thru the body except for an annular shoulder 18 which forms a bottom for each of the bores. It is in these bores that the mechanism is placed for automatically retaining the cutter at all times in contact with the casing. rThis mechanism comprises a bolt 2O of sturdy construction having an enlarged head 21 which may be either conical or spherical as desired. rlhis bolt is approximately the same length as the diameter ot' the body 11 and projects thru a restricted opening 23 in the shoulder 18. Between the underside of the head 21 and the shoulder 18 is placed a strong spring 24 which normally tends to expel the bolt from the bore 16. A. tap 25 is seated in the bore 17 and opposes the pressure ot the spring by being threaded onto the bolt 20. The tap 25 may be hexagonal or square and is adapted to receive a wrench whereby it may be adjusted or removed. It will thus be apparent that by adjusting the tap 25 on the bolt 2O the distance which the head 21 may project out beyond the body 11 can be altered as desired for a purpose which will be later described. l Adjacent the base of the cavity 13, there is shown another pressure mechanism which is similar in most respects to the one just described. However, instead of the tap 25 a tap 30 of special construction is used. This tap 30 is adapted to fit snugly within the bore 31 which is similar to 17; openings 32 are provided in the face of the tap to receive a wrench whereby it may be adjusted. The pel'iphery of this tap 30 may be machined to obtain a valve-like fit with the bore 31. The bolt 2O is also arranged to make a tight sliding fit with the restricted opening 23 in the shoulder 1S.

As is usual the drill stem 15 is hollow and is adapted to form a passage for flushing fluid. The cavity 13 has drilled in its base one or more passages 35 which open into and near the base of the bore 3l. lVhenthe pressure mechanism is in its extended position as here illustrated the tap 30 is seated in the base of the bore 31 and the passageways 35 are open to connect the cavity 13 and bore 31. In this position fluid is free to pass down the drill stem and out the bore 31. However, if the bolt 20 is pressed inwardly the tap 30 slides in the bore 3l and closes the passage 35. l

In the embodiment ofthe invention here illustrated I have shown two of these pressure mechanisms but it is to be understood that if a fewer or greater number are desired they may be provided to meet the existing conditions as encountered in practical use.

Fig. 1 also shows the cutting blade or cutu ter 40 as being pivoted upon a pin 41, which is in turn seated in a groove 42 longitudinally of the body 11. Set screws 43 are threaded into the ends of the groove 42 and retain the pin 41 in a rigid position. The set screws have an opening therein to receive an'appropriate wrench. The cutter 40 is pivoted on the pin 41 for free swinging movement in a transverse slot 44, best seen in Fig. 2. The pin 41 is so situated oft center with respect to the axis of the body 11 that as the blade 40 swings from the position shown in dotted lines on Fig. 2, to the full line or cutting position it is gradually projected out of the slot and beyond the surface of the body 11 to present a cutting blade. A small spring 45 is shown as placed in the slot 44 to prevent the blade from swinging entirely within the slot, but permitting it to be forced within the slot if necessary. It'will be noted that the toe 4G of the blade 40 projects outward from the body 11 a greater distance than the heel 47.

The operation of my casing cutter is as follows: The point 12 is inserted into the easing to be cut, and gradually lowered until the. extended head 21 of the loweimost bolt strikes the casing; continued lowering causes the casing to press this head inwardly and as the cutter 40 is in the dotted line position of Fig. 2 the heel 47 may be pressed into the slot 44, but the spring 45 tends to force it lightly against the casing. The tool is lowered further until the head 21 of the upper bolt also passes into the casing compressing the spring 24 and forcing the tap 8O to a position closing the end of the passage 35. The tool is then lowered to the particular place where the cut is to be made. The two or more bolt heads 21 are constantly forcing the body 11 against the opposite side of the casing. The tool is then rotated usually to the right, the heel 47 of the cutter due to the pressure of the spring 45 engages the casing and after a quarter of a turn, the blade, by this engagement swings to its operating position. This swinging is lopposed by the pressure of the springs 24 as this movement ofthe cutter 40 forces the heads 21 into the bores 16. It will be seen from this recital that the cutter 40 is now in a position to cut into the casing and is held in constant engagement therewith by the pressure of the two springs 24. The tool is now rotated and a cut is gradually formed until the bolt heads 21 assume their extended position due to the cutter passing out thru the casing. Before the cut is started the fluid pump is set in operation filling the stem 15 but as the passages 35 are closed the pressure of the fluid stops the pump. The stem is rotated and as the cut is finished the tap 30 slides past thc passage 35 and allows fluid to flow thercthru, the pressure in the drill stem is thus relieved and the pump again starts. This starting of the pump signifies to the operator that the cut is finished. If he desires to withdraw the tool without bringing the severed piece of casing he backs off with a left hand quarter turn and thus the cutter is rotated to its dotted position, Fig. 2, and an upward pull causes the lower bolt head 2l to pass into the severed casing whereby the tool may then be withdrawn.' The severed casing may if desired be recovered with a spear, grapple or tap but it could be raised by merely withdrawing the tool carrying the severed casing on the cutter blade 40. The tool may be made in any desired size to correspond with the pipe to be cut.

It is believed that the simplicit and ease of operation of my device will e readily apparent as I have disclosed herein an embodiment of my present improvements which I believe to be entirely satisfactory and practical for the purposes now in view, nevertheless it is to be understood that the several essential parts of this improved embodiment might be constructed in various other alternative forms, and it is accordingly to be understood in the further development of the device that I reserve the privilege of resorting to all such legitimate changes therein as may be fairly embodied within the spirit and scope of the invention as claimed.

lVhatfI claim is:

l. A pipe cutter including a body, transversely disposed coaxial bores in said body, an annular shoulder separating said bores, a restricted opening thru said shoulder, a bolt having' a head, disposed in one of said bores and projecting thru said restricted o ening, a spring in said bore and abutting t e bolt head and said shoulder, a ta) in the other of said bores threaded to sai bolt and re- 3. A casing cutter including a body, a cutting blade carried by said body, and non-- cutting means transverselydisposed in said body and adapted to force said body with said blade into cutting engagement with said casing by moving said body laterally to frictionally engage said cutter with said casing.

4. A casing cutter comprising a body, a cutting blade carried at one side of said body, spring pressed means carried by the other side of said body and adapted by engagement with the casing to force the body and said blade against the casing.

5. A. casing cutter including yieldably extended means projecting from said cutter, a cutting blade, retractib-le for insertion'into a casing and so mounted that rotation of said cutter will because of engagement of said blade with the casing tend to compress said yieldable extended means and project the blade.

6. A device of the character described comprising a body, a bolt carried thereby and adapted to press against the casing to be cut, a cutting blade adapted to be projected into cutting engagement, said bolt and said blade being diametrically disposed in said body. 7 A. casing cutter including a body having a iiuid passage therein, means adapted to engage the casing to be cut, means carried by the first said means to close said passage, and a cutting blade adapted to'be forced into the casing by the first said means.

8. A casing cutter including a body, a pivoted blade having a heel and a toe, a slot in which said blade is adapted to pivot, a spring 5 in said slot` whereby the heel of said blade4 normally projects outside of said slot, and means to force the body and therefore the blade heel against the side'of the casing so that rotation of the body will force the blade into the casing.

9. A casing cutterv including a body, a cutting blade mounted therein and movable .from inoperative to operative position responsive to the rotation of said body and spring-pressed means reacting against the wall of the casing. Y

10. A casing cutter including a body, a cutting blade mounted therein, means to engage the casing to force said blade into the cut, and means controlled by said iirst named means to indicate when said cuthas been completed.

11. An inside casing cutter including a body, spring-pressed means normally protruding from the side of said body whereby the cutter is maintained in an eccentric position ,in the casing being cut, a pivotally mounted blade adapted to move to cutting position upon rotation of the cutter, said means opposing the pivoting of said 4blade and exerting a pressure thereon when said blade is extended whereby the casing may be cut.

12. A casing cutter including a body, a

cutting blade carried by said body, and noncutting means transversely disposed in said body and adapted to force said blade into cutting engagement with said casing by moving -said body laterally, said non-cutting means projecting from said body and arranged to engage the' casing being cut diametrically from the cutter.

13. A casing cutter including a body poi'- tion, cutting and non-cutting means arranged to be extended lfrom or retracted into said body, and means to extend said non-cutting means from said body whereby the diameter of the non-cutting means, the body and the cutting means is greater than that of the.

casing being cut. y

14. A casing cutter comprising a body, a cutting blade carried on one side of said body, spring pressed means carried by the other side of said body and adapted by engagement with the casing to force the body away from the side of the casing and thereby force said blade against the casing.

15. A casing cutter comprising in combination a body,a cutting blade pivotally mountifi ed in said body, a pivot Jfor said blade placed on' center of said body, a plurality ot pressure bolts arranged transversely of said body and adapted to press said body against the work, said blade being advanced. by rotation of said body to cutting posit1on, and means controlled by one of said bolts to indicate when the cut has been completed.

16. A casing cutter comprising in combination a body, a cutting blade pivotally mounted in said body, a ivot for said blade v ,-f

placed o center of sai body, a plurality of bolts adapted to press said body against the work, means holding said blade partly extended to engage the pipe and means controlled by one of said bolts to indicate when the cut has been completed.

17. In a device of the character ldescribed, a body, a cutting blade, and non-cutting means adapted to be projected from the side of said body opposite to said blade whereby the blade is constantly retained in engagement with said casing, and a passage in said body opened by movement ofsaid body by said means to casing contacting position.

18. A. device of the character described comprising a drill stemLa cutting tool carried by said stem including a body, a plurality of transversely disposed means carried by said body so arranged as to force said body against the pipe, av cutter mounted to swing transversely in said body and means holding said cutter outwardly Whereby rotation oi' said stem extends said cutter to cutting position and compresses transversely disposed means against the casing.

19. A device of the character described including a body, a normally retracted cutting blade, means normally extended to engage the casing and oppose the movement of said blade to cutting position, said means being adapted to be compresssed upon rotation of said cutting blade.

20. A device of the character described includingl a body, a normally retracted cutting blade, means tending to move said blade outward toward cutting position, means adapted to be compressed upon rotation of said cutting blade to operative position to hold 'said blade in contact With said casing, said blade When open acting to move said body to an eccentric position in the casing being cut.

In testimony whereof l hereunto aiiiX my signature this 5 day of Sept., A. D. 1928.

ELLSWURTF GRAY. 

